JP2018150952A - Pressure shock absorber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress generation of noise accompanied by control of the flow of fluid with a valve.SOLUTION: A hydraulic shock absorber includes a cylinder storing oil, a valve seat 41 forming a flow passage through which the oil flows in accordance with relative movement of a rod in a prescribed direction with respect to the cylinder, an elastic check valve 431 opening and closing an extension side oil passage 413 of the valve seat 41, a retaining structure 414 allowing positional movement of the check valve 431 between a contact position in contact with the valve seat 41 and a remote position away from the valve seat 41, a check valve stopper 432 restricting deflection deformation of the check valve 431 at the remote position, and an elastic imparting member 433 uneven in a circumferential direction of the check valve 431 and imparting a load toward the valve seat 41 to the check valve 431.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a pressure buffering device.

  A pressure buffering device that performs buffering using a fluid is known. For example, in Patent Document 1, a flow path is formed in the bottom piece, a check valve for opening and closing the flow path is provided on one side of the bottom piece, and a coil spring that repels the check valve is fastened by a bolt and a nut provided on the bottom piece In the bottom valve device, the screw direction of the nut (or bolt) for tightening the coil spring and the winding direction of the coil spring are described as opposite directions.

JP 2004-21118A

  By the way, when a valve that controls the flow of fluid by moving the position is adopted, when the valve receives a large pressure of fluid, the valve moves all at once, so that the valve comes into contact with other members to generate sound. There was a fear.

  An object of this invention is to suppress generation | occurrence | production of the sound accompanying control of the flow of the fluid by a valve | bulb.

  For this purpose, the present invention has a cylinder that contains a fluid, a piston that forms a flow path through which the fluid flows as the rod moves relative to the cylinder in a predetermined direction, and has elasticity. A valve that opens and closes the flow path, a movement allowing portion that allows movement of the position of the valve between a contact position that contacts the piston and a separation position that is separated from the piston, and bending deformation of the valve at the separation position The pressure buffer device includes: a restricting portion that restricts the pressure, and an imparting portion that has elasticity and is uneven in the circumferential direction of the valve and applies a load toward the piston side to the valve.

  ADVANTAGE OF THE INVENTION According to this invention, generation | occurrence | production of the sound accompanying control of the flow of the fluid by a valve | bulb can be suppressed.

1 is an overall view of a hydraulic shock absorber according to a first embodiment. It is sectional drawing of the bottom piston part of 1st Embodiment. (A) is a fragmentary sectional view of the bottom piston part of 1st Embodiment, (B) is a top view of the bottom piston part of 1st Embodiment. (A) And (B) is operation | movement explanatory drawing of the hydraulic shock absorber of 1st Embodiment. It is explanatory drawing of the hydraulic shock absorber of 2nd Embodiment. (A) And (B) is explanatory drawing of the hydraulic shock absorber of 3rd Embodiment. It is explanatory drawing of the hydraulic shock absorber of 4th Embodiment. (A) And (B) is explanatory drawing of the hydraulic shock absorber of 5th Embodiment. It is explanatory drawing of the hydraulic shock absorber of 6th Embodiment. It is explanatory drawing of the provision member of a modification.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
<First Embodiment>
[Configuration and function of hydraulic shock absorber 1]
FIG. 1 is an overall view of a hydraulic shock absorber 1 according to the first embodiment.

  As shown in FIG. 1, a hydraulic shock absorber 1 (an example of a pressure shock absorber) is provided with a cylinder portion 10 that contains oil, and the other side protrudes outside the cylinder portion 10 and one side is inside the cylinder portion 10. And a rod 20 to be slidably inserted. Further, the hydraulic shock absorber 1 includes a piston portion 30 provided at one end portion of the rod 20, a bottom piston portion 40 provided at one end portion of the cylinder portion 10, and a radially outer side of the cylinder portion 10. And a damping force variable section 50 provided.

  In the following description, the longitudinal direction of the hydraulic shock absorber 1 shown in FIG. 1 is referred to as an “axial direction”. Further, the lower side in the axial direction is referred to as “one side”, and the upper side of the hydraulic shock absorber 1 is referred to as “the other side”. Moreover, the left-right direction of the hydraulic shock absorber 1 shown in FIG. 1 is referred to as a “radial direction”. In the radial direction, the central axis side is referred to as “radial inner side”, and the side away from the central axis is referred to as “radial outer side”. Further, a rotation direction around the axial direction of the hydraulic shock absorber 1 is referred to as a “circumferential direction”.

[Configuration and function of cylinder part 10]
The cylinder part 10 includes a cylinder 11, an outer cylinder 12 provided on the radially outer side of the cylinder 11, and a damper case 13 provided on the outer side of the outer cylinder 12 in the radial direction.

The cylinder 11 is formed in a cylindrical shape and has a cylinder opening 11H on the other side.
The outer cylinder 12 forms a communication path L between the outer cylinder 12 and the cylinder 11. Further, the outer cylinder 12 has an outer cylinder opening 12 </ b> H at a position facing the damping force variable unit 50.
The damper case 13 forms a reservoir chamber R in which oil is accumulated between the damper case 13 and the outer cylinder 12. The reservoir chamber R absorbs oil in the cylinder 11 (first oil chamber Y1) or supplies oil into the cylinder 11 (first oil chamber Y1) as the rod 20 moves relative to the cylinder 11. . The reservoir chamber R stores oil that has flowed out of the damping force variable unit 50. Further, the damper case 13 has a case opening 13 </ b> H at a position facing the damping force variable portion 50.

[Configuration and function of rod 20]
The rod 20 is a rod-like member that extends long in the axial direction. The rod 20 is connected to the piston part 30 on one side. Further, the rod 20 is connected to the vehicle body side via a connecting member or the like (not shown) on the other side.

[Configuration and function of piston part 30]
The piston portion 30 is provided between a piston body 31 having a plurality of piston oil passage ports 311, a piston valve 32 that opens and closes the other side of the piston oil passage ports 311, and one end portion of the piston valve 32 and the rod 20. And a spring 33. And the piston part 30 partitions the oil in the cylinder 11 into the 1st oil chamber Y1 and the 2nd oil chamber Y2.

[Configuration and function of bottom piston 40]
The bottom piston portion 40 is provided in the axial direction with a valve seat 41 (an example of a piston), a damping valve portion 42 provided on one side of the valve seat 41, a check valve portion 43 provided on the other side of the valve seat 41. The fixing member 44 is provided. The bottom piston portion 40 separates the first oil chamber Y1 and the reservoir chamber R.
The valve seat 41, the damping valve portion 42, the check valve portion 43, and the fixing member 44 of the bottom piston portion 40 will be described in detail later.

[Configuration and function of damping force variable section 50]
The damping force variable unit 50 includes a solenoid unit 51, a connection flow path member 52, and a solenoid valve 55.
The solenoid unit 51 moves the plunger 51P forward and backward based on control by a control unit (not shown).
The connection flow path member 52 is a member formed in a substantially cylindrical shape having a connection flow path 52R inside.
The solenoid valve 55 changes the cross-sectional area of the oil in the connection flow path 52R in accordance with the movement of the position with respect to the connection flow path member 52. And the solenoid valve 55 restrict | squeezes the flow of the oil in the connection flow path 52R.
In the first embodiment, the damping force in the hydraulic shock absorber 1 is mainly generated by restricting the oil flow by the solenoid valve 55.

FIG. 2 is a cross-sectional view of the bottom piston portion 40 of the first embodiment.
FIG. 3A is a partial cross-sectional view of the bottom piston portion 40 of the first embodiment, and FIG. 3B is a top view of the bottom piston portion 40 of the first embodiment.

(Valve seat 41)
As shown in FIG. 2, the valve seat 41 includes a through hole 41 </ b> H formed on the radially inner side, a pressure side oil passage 412 formed on the radially outer side of the through hole 41 </ b> H, and a radially outer side of the pressure side oil passage 412. And an extension side oil passage 413 to be formed. Further, the valve seat 41 includes a holding structure portion 414 formed on the other side, an inner round portion 415 (an example of an inner annular portion) formed on the other side, and an outer round portion 416 (outer side) formed on the other side. An example of an annular portion). Further, the valve seat 41 has a reservoir channel portion 417 formed on one side.

  The through hole 41H is formed extending in the axial direction of the valve seat 41. And the fixing member 44 is inserted in the through-hole 41H.

A plurality (four in this embodiment) of pressure side oil passages 412 are provided at substantially equal intervals in the circumferential direction. The pressure-side oil passage 412 forms a first other-side oil passage port P1 at the other end portion and a first one-side oil passage port P3 at one end portion.
The pressure-side oil passage 412 enables oil to flow between the first oil chamber Y1 and the reservoir chamber R during the compression stroke of the hydraulic shock absorber 1 (see FIG. 1).

A plurality of extension side oil passages 413 (four in this embodiment) are provided at substantially equal intervals in the circumferential direction. The extension-side oil passage 413 forms a second other-side oil passage port P2 at the other end portion and a second one-side oil passage port P4 at one end portion.
The extension-side oil passage 413 enables oil to flow between the reservoir chamber R and the first oil chamber Y1 during the expansion stroke of the hydraulic shock absorber 1 (see FIG. 1).

The holding structure portion 414 (an example of a movement allowing portion) is formed in a substantially annular shape on the outer periphery of the through hole 41H. And the holding | maintenance structure part 414 protrudes in an axial direction toward the other side. The holding structure portion 414 forms a space (a gap C described later) that allows the position of the check valve 431 to move in the axial direction.
As shown in FIG. 3A, the holding structure portion 414 of the first embodiment has a side surface 414T formed in a tapered shape. Specifically, the holding structure portion 414 has a smaller outer diameter on the other side than the one side. Accordingly, in the first embodiment, the position of a check valve 431 described later can be moved smoothly in the axial direction.

  The inner round portion 415 is formed in an annular shape on the radially outer side of the first other-side oil passage port P1 and on the radially inner side of the second other-side oil passage port P2 (see FIG. 2). The inner round portion 415 protrudes in the axial direction toward the other side. And the inner side round part 415 of 1st Embodiment forms the contact location with the check valve 431 mentioned later. Furthermore, the inner round part 415 suppresses the flow of oil between the first other-side oil passage port P1 and the second other-side oil passage port P2 (see FIG. 2) together with a check valve 431 described later.

  The outer round portion 416 is formed in an annular shape on the radially outer side of the second other-side oil passage port P2 (see FIG. 2). Further, the outer round part 416 protrudes in the axial direction toward the other side. The protruding height in the axial direction of the outer round portion 416 is formed slightly higher than that of the inner round portion 415. And the outer round part 416 forms the contact location with the below-mentioned check valve 431.

  In the first embodiment, a surface passing through the inner round portion 415 and the outer round portion 416 is referred to as a round surface 41P.

  The reservoir channel portion 417 is an opening formed at one end. The reservoir channel portion 417 faces the first one-side oil passage port P3, the damping valve portion 42, and the second one-side oil passage port P4 on the radially inner side. The reservoir channel portion 417 is connected to the reservoir chamber R (see FIG. 1) on the outer side in the radial direction.

(Damping valve part 42)
As shown in FIG. 2, the damping valve unit 42 includes a damping valve 421 and a pressure side ring seat 422 provided on one side of the damping valve 421.

The damping valve 421 is a disk-shaped metal plate through which the fixing member 44 penetrates radially inward. The outer periphery of the damping valve 421 is formed on the radially outer side of the first one-side oil passage port P3 and on the radially inner side of the second one-side oil passage port P4.
Further, the thickness of the damping valve 421 of the first embodiment is formed larger than the thickness of a check valve 431 described later.
The damping valve 421 configured as described above opens and closes the first one-side oil passage port P3 and always opens the second one-side oil passage port P4.

  The compression side ring seat 422 is a disk-shaped metal plate through which the fixing member 44 penetrates radially inward. The outer diameter of the compression side ring seat 422 is smaller than that of the damping valve 421. And the compression side ring seat 422 ensures the deformation | transformation area | region at the time of the damping valve 421 deform | transforming toward one side.

  The attenuation valve 421 may be formed of a plurality of (for example, three) metal plates. Even in this case, the total thickness of the damping valve 421 is made larger than the thickness of the check valve 431 described later.

(Check valve part 43)
As shown in FIG. 2, the check valve unit 43 includes a check valve 431 (an example of a valve) provided on the other side of the valve seat 41 and a check valve stopper 432 (an example of a limiting unit) provided on the other side of the check valve 431. ), An application member 433 (an example of an application unit) provided on the other side of the check valve stopper 432, and a collar member 434 provided on the other side of the application member 433.

As shown in FIG. 3A, the check valve 431 is a disk-shaped metal plate having an opening 431H through which the holding structure portion 414 passes on the inner side in the radial direction. The outer periphery of the check valve 431 is located on the outer round portion 416.
Note that the outer periphery of the check valve 431 may be located on the radially outer side of the outer round portion 416.

The check valve 431 includes a check valve oil passage port 431M formed on the radially outer side of the opening 431H and a slit 431S formed on the radially outer side of the check valve oil passage port 431M.
The check valve oil passage port 431M is formed at a position corresponding to the first other-side oil passage port P1 in the radial direction. A plurality of check valve oil passage ports 431M are provided. The check valve oil passage port 431M is provided to face the first other-side oil passage port P1.

  The slit 431S is formed by a notch formed on the outer periphery of the check valve 431 toward the radially inner side. The slit 431 </ b> S is provided to face the outer round portion 416. The slit 431S is in the extension side oil passage 413 even when the check valve 431 is totally deformed and the second other side oil passage port P2 is not opened when the rod 20 moves at a very low speed during the extension side stroke. Allows the oil to flow through.

The check valve 431 configured as described above opens and closes the second other-side oil passage port P2, and always opens the first other-side oil passage port P1. The check valve 431 according to the first embodiment restricts the flow of oil through the extension side oil passage 413 when the rod 20 moves in one direction, and the extension side oil moves when the rod 20 moves in the other direction. The oil flow through the path 413 is allowed.
In the hydraulic shock absorber 1 of the first embodiment, the check valve 431 is a member that does not mainly generate the damping force and switches the oil flow in the extension side oil passage 413.

  As shown in FIG. 3A, the check valve stopper 432 is a substantially annular metal plate having an opening 432H through which the fixing member 44 is passed in the radial direction. As shown in FIG. 3A, the check valve stopper 432 has an outer diameter larger than that of the holding structure portion 414. Therefore, the check valve stopper 432 protrudes radially outward with respect to the holding structure portion 414.

The check valve stopper 432 is provided in the axial direction with a predetermined gap C with respect to the round surface 41P of the valve seat 41. Accordingly, the check valve 431 is movable between a contact position that contacts the round surface 41P and a separated position that is separated from the round surface 41P.
In addition, the check valve stopper 432 limits the deformation of the check valve 431 at a position far from the round surface 41P.

Here, in the first embodiment, the contact position is a position where all of the check valves 431 are in contact with the round surface 41P. In addition, the separation position is a position where all of the check valves 431 are separated from the round surface 41P.
Note that the movement of the position of the check valve 431 can also be regarded as the displacement of the check valve 431 as a whole in the axial direction. In this case, the movement of the position of the check valve 431 can be regarded as a displacement in a state where the check valve 431 is not deformed.
Further, the deformation of the check valve 431 means that the radially outer side (at least the opposite part of the second other-side oil passage port P2) is deformed in a state where the radially inner side (opening 432H side) is located at the second position. It can also be taken as.

As shown in FIG. 3A, the applying member 433 is a member having an opening 433H through which the fixing member 44 and the collar member 434 are passed on the radially inner side. And the provision member 433 has elasticity. For example, a metal such as iron can be used as the material of the applying member 433.
Then, the applying member 433 applies a load that is uneven in the circumferential direction of the check valve 431 and directed toward the valve seat 41 to the check valve 431. Hereinafter, the applying member 433 will be described in detail.

As shown in FIG. 3B, the applying member 433 includes a first outer protruding portion 433A (an example of a contact portion), a second outer protruding portion 433B, and a held portion 433R.
The first outer protrusion 433A is radially outward and protrudes toward one side. A plurality of first outer protrusions 433A are provided and are arranged at substantially equal intervals in the circumferential direction. And 1st outer side protrusion part 433A contacts the surface of the other side of the check valve 431 in the contact end part E1 (refer FIG. 3 (A)).

The second outer protrusion 433B protrudes radially outward and toward the other side. A plurality of second outer protrusions 433B are provided and are arranged at substantially equal intervals in the circumferential direction.
In the first embodiment, the second outer protrusion 433B does not contact other members and is a free end. In the first embodiment, by providing the second outer protrusion 433B in a symmetric relationship with the first outer protrusion 433A, for example, in the case of assembling the apparatus, when the applying member 433 is attached opposite to the first embodiment Even so, it works in the same way.

  The first outer protrusions 433A and the second outer protrusions 433B are alternately arranged in the circumferential direction. Further, a notch 433K is formed between the first outer protrusion 433A and the second outer protrusion 433B.

  As shown in FIG. 3 (A), the contact end E1 of the first outer protrusion 433A of the applying member 433 of the first embodiment is radially outer than the inner round part 415, and is an outer round part. The check valve 431 comes into contact with a region radially inward of 416.

  And the to-be-held part 433R of 1st Embodiment is comprised by the some shape part. In the following description, each shape portion is referred to as a first shape portion 433R1, a second shape portion 433R2, a third shape portion 433R3, a fourth shape portion 433R4, a fifth shape portion 433R5, and a sixth shape portion 433R6. In addition, when not distinguishing these some shape parts in particular, it will generically call the shape part of the to-be-held part 433R.

The shape portion of the held portion 433R protrudes inward in the radial direction. Further, the width in the circumferential direction of the shape portion of the held portion 433R is formed in a tapered shape that is smaller on the radially inner side than on the radially outer side. The taper angles of the plurality of shape portions of the held portion 433R are the same. Further, the plurality of shape portions of the held portion 433R are arranged so that the lines L1 along the radial direction passing through the respective centers are equally spaced in the circumferential direction.
Further, the shape portion of the held portion 433R is provided at a position facing the notch portion 433K. Specifically, the plurality of shape portions of the held portion 433R are arranged so as to be aligned with the cutout portion 433K along the radial direction.
3A, the inner side in the radial direction of the held portion 433R is sandwiched between the check valve stopper 432 and the collar member 434.

  In the first embodiment, the plurality of shape portions of the held portion 433R have different widths in the circumferential direction. Thereby, in the provision member 433 of the first embodiment, the strength of the held portion 433R is varied in the circumferential direction. The applying member 433 according to the first embodiment applies a load that is uneven in the circumferential direction of the check valve 431 and directed toward the valve seat 41 to the check valve 431. Hereinafter, the width in the circumferential direction of each held portion 433R will be described in detail.

In the first embodiment, the width B1 of the first shape portion 433R1 is the largest compared to the other held portions 433R. Further, the width B4 of the fourth shape portion 433R4 is the smallest as compared with the other held portions 433R.
3B, the width B1 of the first shape portion 433R1, the width B2 of the second shape portion 433R2, the width B3 of the third shape portion 433R3, and the width B4 of the fourth shape portion 433R4 in the order clockwise. The width is smaller.
3B, the width B1 of the first shape portion 433R1, the width B6 of the sixth shape portion 433R6, the width B5 of the fifth shape portion 433R5, and the width B4 of the fourth shape portion 433R4 are counterclockwise. The width is getting smaller.
The width B2 of the second shape portion 433R2 and the width B6 of the sixth shape portion 433R6 are substantially the same. Further, the width B3 of the third shape portion 433R3 and the width B5 of the fifth shape portion 433R5 are substantially the same.

  As described above, the plurality of held portions 433R of the first embodiment have uneven circumferential widths.

  Further, in the hydraulic shock absorber 1 of the first embodiment, the check valve 431 is not a main purpose of generating a damping force, but is a member that switches the oil flow in the extension side oil passage 413.

As shown in FIG. 3A, the collar member 434 has a small diameter portion 434N and a large diameter portion 434W provided on the other side of the small diameter portion 434N. Further, the collar member 434 is configured separately from a later-described nut 442 of the fixing member 44.
The small diameter portion 434N contacts the check valve stopper 432 on one side. Further, the small diameter portion 434N contacts the held portion 433R of the applying member 433 in the radial direction. The small diameter portion 434N determines the position of the applying member 433 in the radial direction.
The large diameter portion 434W protrudes outward in the radial direction from the small diameter portion 434N. The large diameter portion 434W faces the other side of the held portion 433R of the applying member 433.

(Fixing member 44)
As shown in FIG. 2, the fixing member 44 includes a bolt 441 provided on one side and a nut 442 provided on the other side. The fixing member 44 fixes the damping valve portion 42 and the check valve portion 43 to the valve seat 41, respectively.

[Operation of hydraulic shock absorber 1]
FIG. 4 is an operation explanatory diagram of the hydraulic shock absorber 1 according to the first embodiment. 4A shows the oil flow during the expansion stroke, and FIG. 4B shows the oil flow during the compression stroke.
First, the operation of the hydraulic shock absorber 1 during the expansion stroke will be described.
As shown in FIG. 4A, the rod 20 moves to the other side with respect to the cylinder 11 during the extension stroke. At this time, the piston valve 32 remains blocking the piston oil passage port 311. Further, the volume of the second oil chamber Y2 decreases due to the movement of the piston portion 30 to the other side. Then, the oil in the second oil chamber Y2 flows out from the cylinder opening 11H to the communication path L.

  Further, the oil flows into the damping force variable unit 50 through the communication path L, the outer cylinder opening 12H, and the connection flow path 52R. In the damping force variable unit 50, the flow of the oil in the connection flow path 52 </ b> R is throttled by the solenoid valve 55. A damping force is generated when the oil flow is throttled by the solenoid valve 55. Thereafter, the oil flows out into the reservoir chamber R.

Further, the pressure in the first oil chamber Y1 is relatively low with respect to the reservoir chamber R. Therefore, the oil in the reservoir chamber R flows into the extension side oil passage 413 of the bottom piston portion 40.
At this time, the check valve 431 of the first embodiment moves to the other side against the spring force of the applying member 433. Further, the check valve 431 is bent and deformed from the radially outer side to the radially inner side. As described above, the check valve 431 of the first embodiment causes both the movement of the position of the check valve 431 in the axial direction and the bending deformation of the check valve 431 when the extension side oil passage 413 is opened. Thereafter, the oil flows into the first oil chamber Y1.

  As described above, the check valve 431 according to the first embodiment performs both the movement of the position and the bending deformation. As a result, the force applied to the check valve 431 is distributed to the movement of the position of the check valve 431 accompanying the deformation of the applying member 433 and the bending deformation of the check valve 431 itself. Therefore, compared with the case where the check valve 431 only moves its position without bending deformation, the check valve 431 does not move at a stretch, and the generation of a loud sound accompanying the movement of the position of the check valve 431 is suppressed. Further, the amount of deformation of the check valve 431 is reduced and the load applied to the check valve 431 is reduced as compared with the case where the check valve 431 only moves its position without bending deformation.

  Furthermore, in the provision member 433 of the first embodiment, the plurality of held portions 433R have different widths in the circumferential direction. Therefore, the load based on the spring force applied by the applying member 433 to the check valve 431 differs in the circumferential direction of the check valve 431. Therefore, when the check valve 431 opens the extension side oil passage 413, the timing at which the check valve 431 is separated from the round surface 41P is different in the circumferential direction.

In the first embodiment, for example, the load with which the fourth shape portion 433R4 having the smallest circumferential width presses the check valve 431 becomes the smallest. In addition, for example, the load with which the first shape portion 433R1 having the largest width in the circumferential direction presses the check valve 431 becomes the largest.
Accordingly, the check valve 431 starts to open (separate) from a position facing the fourth shape portion 433R4. Finally, in the check valve 431, the portion facing the first shape portion 433R1 is finally opened (separated).
Thus, in 1st Embodiment, generation | occurrence | production of a sound is suppressed more because the check valve 431 moves and deform | transforms in order in the circumferential direction.

Next, the operation of the hydraulic shock absorber 1 during the compression stroke will be described.
As shown in FIG. 4B, the rod 20 moves relative to the cylinder 11 to one side during the compression stroke. In the piston part 30, the piston valve 32 that closes the piston oil passage port 311 is opened by the differential pressure between the first oil chamber Y1 and the second oil chamber Y2. Then, the oil in the first oil chamber Y1 flows out to the second oil chamber Y2 through the piston oil passage port 311. Here, the rod 20 is disposed in the second oil chamber Y2. Therefore, the oil flowing from the first oil chamber Y1 into the second oil chamber Y2 becomes excessive by the approach volume of the rod 20. Accordingly, an amount of oil corresponding to the approach volume of the rod 20 flows out from the cylinder opening 11H to the communication path L.

  Further, the oil flows into the damping force variable unit 50 through the communication path L, the outer cylinder opening 12H, and the connection flow path 52R. Note that the oil flow in the damping force varying unit 50 is the same as the oil flow during the extension stroke described above.

  Further, as the rod 20 moves relative to the cylinder 11 to one side, the oil in the first oil chamber Y1 passes through the opening 433H of the applying member 433 of the bottom piston portion 40 and the check valve oil passage port 431M ( 2) and flows into the pressure side oil passage 412. Then, the oil that has flowed into the pressure side oil passage 412 opens the damping valve 421. Then, the oil flows out to the reservoir chamber R. That is, a damping force is generated by both the flow of oil flowing from the cylinder opening 11H to the damping force variable portion 50 and the oil flow in the bottom piston portion 40 according to the pressure in the first oil chamber Y1.

In particular, the imparting member 433 acts so that the check valve 431 immediately closes the second other-side oil passage port P2 when the check valve 431 opened in the extension stroke shifts to the compression stroke. As a result, the generation of the damping force in the initial stage of the compression stroke (so-called rising of the damping force) is accelerated.
Furthermore, in the first embodiment, since the applying member 433 is in contact with the check valve 431 on the radially outer side of the inner round part 415 and on the radially inner side of the outer round part 416, the check valve 431 is on the inner side. By contacting both the round part 415 and the outer round part 416 with no gap, oil leakage is suppressed.

  By the way, when the damping force is adjusted by the damping force variable unit 50, the solenoid valve 55 is controlled by the solenoid unit 51 (see FIG. 1). Specifically, the distance between the solenoid valve 55 and the connection flow path member 52 is changed by the solenoid unit 51. At this time, if the distance between the solenoid valve 55 and the connection flow path member 52 becomes narrow, the resistance of the oil flow increases and the damping force increases. On the other hand, if the interval between the solenoid valve 55 and the connection flow path member 52 is widened, the resistance of the oil flow is reduced and the damping force is reduced.

Second Embodiment
FIG. 5 is an explanatory diagram of the hydraulic shock absorber 1 according to the second embodiment.
Note that in the second embodiment, members similar to those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the hydraulic shock absorber 1 of the second embodiment, the structure of the second application member 533 of the bottom piston portion 40 is different from the application member 433 of the first embodiment.

The second provision member 533 is a member having an opening 533H through which the fixing member 44 and the collar member 434 are passed on the radially inner side. And the 2nd provision member 533 has elasticity. In addition, as a material of the 2nd provision member 533, metals, such as iron, can be used, for example.
And the 2nd provision member 533 has the 1st outside projection part 533A, the 2nd outside projection part 533B, and held part 533R.
The first outer protrusion 533A and the second outer protrusion 533B are the same as the first outer protrusion 433A and the second outer protrusion 433B of the first embodiment, respectively.
Also in the second embodiment, the contact end E2 of the first outer protrusion 533A is a check valve in a range radially outside the inner round portion 415 and radially inner than the outer round portion 416. 431 is contacted.

  The held portion 533R of the second embodiment is configured by a plurality of shape portions. In the following description, each shape portion is referred to as a first shape portion 533R1, a second shape portion 533R2, a third shape portion 533R3, a fourth shape portion 533R4, a fifth shape portion 533R5, and a sixth shape portion 533R6. In addition, when not distinguishing these several shape parts in particular, it will generically call the shape part of the to-be-held part 533R.

  The shape portion of the held portion 533R protrudes inward in the radial direction. Further, the width in the circumferential direction of the shape portion of the held portion 533R is formed in a tapered shape that is smaller on the radially inner side than on the radially outer side. The plurality of shape portions of the held portion 533R have substantially the same shape.

The plurality of shape portions of the held portion 533R are arranged such that the lines L1 along the radial direction passing through the respective centers have different intervals in the circumferential direction. That is, in 2nd Embodiment, the space | interval of the shape part of the two to-be-held parts 533R adjacent in the circumferential direction differs in the circumferential direction. Thus, in the second application member 533 of the second embodiment, the strength of the held portion 533R is varied in the circumferential direction. The second application member 533 of the second embodiment applies a load toward the valve seat 41 that is uneven in the circumferential direction of the check valve 431 and directed toward the valve seat 41.
Hereinafter, the interval between the held portions 533R will be described in detail.

  Here, an interval between the sixth shape portion 533R6 and the first shape portion 533R1 is referred to as an “interval W1”. The interval between the first shape portion 533R1 and the second shape portion 533R2 is referred to as “interval W2.” The interval between the second shape portion 533R2 and the third shape portion 533R3 is referred to as “interval W3”. The interval between the third shape portion 533R3 and the fourth shape portion 533R4 is referred to as “interval W4”. The interval between the fourth shape portion 533R4 and the fifth shape portion 533R5 is referred to as “interval W5”. The interval between the fifth shape portion 533R5 and the sixth shape portion 533R6 is referred to as “interval W6”.

  In 2nd Embodiment, the space | interval W1 is the smallest compared with the space | interval of two other held parts 533R adjacent. Further, the interval W4 is the largest compared to the interval between the other two held portions 533R adjacent to each other.

  Then, the intervals increase in the order of the interval W1, the interval W2, the interval W3, and the interval W4 in the clockwise direction in FIG. Further, the interval W increases in the order of the interval W1, the interval W6, the interval W5, and the interval W4 counterclockwise in FIG. Note that the interval W2 and the interval W6 are substantially the same. Further, the interval W3 and the interval W5 are substantially the same.

  As described above, in the second application member 533 of the second embodiment, the interval between the two held portions 533R adjacent to each other is uneven in the circumferential direction.

In the second application member 533 according to the second embodiment configured as described above, the plurality of held portions 533R have different intervals W between adjacent held portions 533R in the circumferential direction. Therefore, the load based on the spring force that the second applying member 533 applies to the check valve 431 differs in the circumferential direction of the check valve 431. Therefore, when the check valve 431 opens the extension side oil passage 413, the timing at which the check valve 431 moves away from the round surface 41P (see FIG. 3A) differs in the circumferential direction.
And also in 2nd Embodiment, generation | occurrence | production of a sound is suppressed more because the position of the check valve 431 moves and deforms in order in the circumferential direction.

<Third Embodiment>
FIG. 6 is an explanatory diagram of the hydraulic shock absorber 1 according to the third embodiment.
Note that in the third embodiment, members that are the same as in the other embodiments are given the same reference numerals, and detailed descriptions thereof are omitted.

  In the hydraulic shock absorber 1 of the third embodiment, the structure of the third application member 633 of the bottom piston portion 40 is different from the application member 433 of the first embodiment.

As shown in FIG. 6A, the third provision member 633 is a member having an opening 633H through which the fixing member 44 and the collar member 434 are passed on the radially inner side. And the 3rd provision member 633 has elasticity. In addition, as a material of the 3rd provision member 633, metals, such as iron, can be used, for example.
As shown in FIG. 6B, the third applying member 633 includes a first outer protruding portion 633A, a second outer protruding portion 633B, a held portion 633R, and an inner protruding portion 633P. Yes.
The held portion 633R is the same as the held portion 433R of the first embodiment.

  And 1st outer side protrusion part 633A is comprised by the some shape part. In the following description, each shape portion is referred to as a first shape portion 633A1, a second shape portion 633A2, a third shape portion 633A3, a fourth shape portion 633A4, a fifth shape portion 633A5, and a sixth shape portion 633A6. In addition, when not distinguishing these several shape parts in particular, it will generically call the shape part of 1st outer side protrusion part 633A.

The shape portion of the first outer protrusion 633A is radially outward and protrudes toward one side. Further, the plurality of shape portions of the first outer protrusion 633A are arranged at substantially equal intervals in the circumferential direction. The shape portion of the first outer protrusion 633A is in contact with the other surface of the check valve 431 at the contact end E3.
As shown in FIG. 6A, also in the third embodiment, the contact end portion E3 is in a range radially outside the inner round portion 415 and radially inward from the outer round portion 416. To contact the check valve 431.

  In the third embodiment, the plurality of shape portions of the first outer protrusion 633A have different protrusion amounts toward one side. That is, the plurality of shape portions of the first outer protrusion 633A are different in distance from the check valve 431. The third application member 633 of the third embodiment applies a load that is uneven in the circumferential direction of the check valve 431 and directed toward the valve seat 41 to the check valve 431. Hereinafter, the amount of protrusion toward one side of each first outer protrusion 633A will be described in detail.

In 3rd Embodiment, as shown to FIG. 6 (A), protrusion amount T1 of 1st shape part 633A1 is the largest compared with the other 1st outer side protrusion part 633A. That is, the first shape portion 633A1 is closest to the check valve 431 as compared with the other first outer protrusion 633A. Further, the protrusion amount T4 of the fourth shape portion 633A4 is the smallest as compared with the other first outer protrusion portions 633A. That is, the fourth shape portion 633A4 is farthest from the check valve 431 as compared to the other first outer protrusion 633A.
Then, in the clockwise direction in FIG. 6B, the protrusion amount T1 of the first shape portion 633A1, the protrusion amount of the second shape portion 633A2, the protrusion amount of the third shape portion 633A3, and the protrusion amount T4 of the fourth shape portion 633A4. In order, the amount of protrusion toward one side decreases.
Further, in FIG. 6B, in the counterclockwise direction, the protrusion amount T1 of the first shape portion 633A1, the protrusion amount of the sixth shape portion 633A6, the protrusion amount of the fifth shape portion 633A5, the protrusion amount T4 of the fourth shape portion 633A4. In this order, the amount of protrusion toward one side decreases.
Note that the protruding amount of the second shape portion 633A2 and the protruding amount of the sixth shape portion 633A6 are substantially the same. Further, the protruding amount of the third shape portion 633A3 and the protruding amount of the fifth shape portion 633A5 are substantially the same.

  The second outer protrusion 633B is opposite in the axial direction to the first outer protrusion 633A in the axial direction, but the basic structure is the same as that of the first outer protrusion 633A.

A plurality of inner protrusions 633P are provided and protrude inward in the radial direction. Note that the protruding amount of the inner protruding portion 633P is smaller than that of the held portion 633R.
The inner protrusion 633P is provided between a plurality of outer protrusions that are between the first outer protrusion 633A and the second outer protrusion 633B. That is, the inner protrusion 633P is provided at a position facing the notch 633K. More specifically, the inner protrusion 633P is arranged so as to be aligned with the notch 633K along the radial direction.

  In the third application member 633 of the third embodiment, the held portion 633R and the inner protrusion 633P are located at positions facing the notch 633K formed between the first outer protrusion 633A and the second outer protrusion 633B. , Respectively, to reduce the stress concentration in the notch 633K.

  In the third application member 633 of the third embodiment configured as described above, the plurality of shape portions of the first outer protrusion 633A have different protrusion amounts toward one side. That is, the plurality of shape portions of the first outer protrusion 633A have different distances from the check valve 431. Thereby, in the third application member 633 of the third embodiment, the load based on the spring force applied in the circumferential direction of the check valve 431 is different in the circumferential direction of the check valve 431.

  In the bottom piston portion 40 of the third embodiment configured as described above, when the check valve 431 opens the extension-side oil passage 413, the check valve 431 is separated from the round surface 41P (see FIG. 3A). Timing is different in the circumferential direction. Also in the third embodiment, the check valve 431 is moved and deformed in order in the circumferential direction, so that the generation of sound is further suppressed.

<Fourth embodiment>
FIG. 7 is an explanatory diagram of the hydraulic shock absorber 1 according to the fourth embodiment.
In the fourth embodiment, members similar to those of the other embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  In the hydraulic shock absorber 1 of the fourth embodiment, the structure of the fourth application member 733 of the bottom piston portion 40 is different from the application member 433 of the first embodiment.

As shown in FIG. 7, the fourth imparting member 733 is a member having an opening 733 </ b> H through which the fixing member 44 and the collar member 434 are passed on the radially inner side. And the 4th provision member 733 has elasticity. In addition, as a material of the 4th provision member 733, metals, such as iron, can be used, for example.
The fourth applying member 733 includes a first outer protrusion 733A, a second outer protrusion 733B, a held portion 733R, and an inner protrusion 733P.
The first outer protrusion 733A, the second outer protrusion 733B, and the inner protrusion 733P are the same as the first outer protrusion 633A, the second outer protrusion 633B, and the inner protrusion 633P of the third embodiment, respectively. .

The held portion 733R protrudes inward in the radial direction. Further, the width of the held portion 733R in the circumferential direction is formed in a tapered shape that is smaller on the radially inner side than on the radially outer side. Further, a plurality of held portions 733R are provided and are arranged at substantially equal intervals in the circumferential direction. The plurality of held portions 733R are formed in substantially the same shape.
The inner side in the radial direction of the held portion 733R is sandwiched between the check valve stopper 432 and the collar member 434.

And in 4th Embodiment, the space | interval I of the to-be-held part 733R, 1st outer side protrusion part 733A, and 2nd outer side protrusion part 733B differs in the circumferential direction. That is, in the fourth embodiment, it can be understood that the lengths of the plurality of held portions 733R are different.
Specifically, the first interval I1 is the smallest compared to the other intervals I. Further, the fourth interval I4 is the largest compared to the other intervals I.
Then, in the clockwise direction in FIG. 7, the interval I increases in the order of the first interval I1, the second interval I2, the third interval I3, and the fourth interval I4. Further, in the counterclockwise direction in FIG. 7, the interval I increases in the order of the first interval I1, the sixth interval I6, the fifth interval I5, and the fourth interval I4.
The second interval I2 and the sixth interval I6 are substantially the same. The third interval I3 and the fifth interval I5 are substantially the same.

  Accordingly, in the fourth embodiment, the position of the contact end E4 where the first outer protrusion 733A contacts the check valve 431 in the circumferential direction of the check valve 431 is different in the radial direction. That is, in the fourth embodiment, the contact positions of the plurality of first outer protrusions 733A with respect to the check valve 431 are different in the circumferential direction. And the 4th provision member 733 of a 4th embodiment gives the load which was uneven in the peripheral direction of check valve 431, and directed toward valve seat 41 to check valve 431.

  Also in the fourth embodiment, the contact end E4 of the first outer protrusion 733A is a check valve in a range radially outside the inner round portion 415 and radially inward from the outer round portion 416. 431 (see FIG. 2).

In the fourth application member 733 of the fourth embodiment configured as described above, the plurality of first outer protrusions 733A have different positions in the radial direction. Therefore, the load based on the spring force that the fourth applying member 733 applies to the check valve 431 differs in the circumferential direction of the check valve 431. Therefore, when the check valve 431 opens the extension side oil passage 413, the timing at which the check valve 431 moves away from the round surface 41P (see FIG. 3A) differs in the circumferential direction.
And also in 4th Embodiment, generation | occurrence | production of a sound is suppressed more because the position of the check valve 431 moves and deforms in order in the circumferential direction.

<Fifth Embodiment>
FIG. 8 is an explanatory diagram of the hydraulic shock absorber 1 according to the fifth embodiment.
Note that in the fifth embodiment, members similar to those of the other embodiments are given the same reference numerals, and detailed descriptions thereof are omitted.

  In the hydraulic shock absorber 1 of the fifth embodiment, the structures of the fifth application member 833 and the collar member 834 of the bottom piston portion 40 are different from those of the application member 433 and the color member 434 of the first embodiment, respectively.

  As shown in FIG. 8A, the fifth application member 833 is a member having an opening portion 833H through which the fixing member 44 and the collar member 834 pass on the radially inner side. And the 5th provision member 833 has elasticity. In addition, as a material of the 5th provision member 833, metals, such as iron, can be used, for example.

As shown in FIG. 8B, the fifth applying member 833 has a first outer protrusion 833A, a second outer protrusion 833B, a held part 833R, and an inner protrusion 833P.
The first outer protrusion 833A and the second outer protrusion 833B are the same as the first outer protrusion 433A and the second outer protrusion 433B of the first embodiment. The held portion 833R and the inner protruding portion 833P are the same as the held portion 633R and the inner protruding portion 633P of the third embodiment. That is, in the fifth applying member 833, the plurality of first outer protrusions 833A, the plurality of second outer protrusions 833B, the plurality of held parts 833R, and the plurality of inner protrusions 833P are formed in substantially the same shape. Are arranged at equal intervals.

As shown in FIG. 8A, the collar member 834 has a small diameter portion 834N and a large diameter portion 834W provided on the other side of the small diameter portion 834N.
In the small diameter portion 834N of the fifth embodiment, the distance (outer diameter) from the center (for example, the center in the radial direction of the fixing member 44, the valve seat 41, and the check valve 431) to the outer periphery is not constant in the circumferential direction but is different. . That is, the small diameter portion 834N draws a circle that is eccentric with respect to the center. Specifically, the small diameter portion 834N includes a first small diameter portion R1 and a second small diameter portion R2 provided at a position different from the first small diameter portion R1 in the circumferential direction. The length in the radial direction of the first small diameter portion R1 is a distance r1. Further, the length in the radial direction of the second small diameter portion R2 is a distance r2 longer than the distance r1.
The small diameter portion 834N comes into contact with the held portion 833R of the fifth applying member 833 in the radial direction. At this time, the small diameter portion 834N determines the position of the fifth applying member 833 in the radial direction.

  And in the 5th provision member 833 of a 5th embodiment, the contact end part E5 of a plurality of 1st outside projections 833A differs in the contact position in the radial direction of check valve 431, respectively. And the 5th provision member 833 of a 5th embodiment imparts the load which was uneven in the peripheral direction of check valve 431, and directed to valve seat 41 to check valve 431.

  In the fifth embodiment, the contact end E5 of the first outer protrusion 833A is a check valve in a range radially outside the inner round portion 415 and radially inward from the outer round portion 416. 431 is contacted.

  In the bottom piston portion 40 of the fifth embodiment configured as described above, when the check valve 431 opens the extension-side oil passage 413, the check valve 431 is separated from the round surface 41P (see FIG. 3A). Timing is different in the circumferential direction. And also in 5th Embodiment, generation | occurrence | production of a sound is suppressed more because the check valve 431 moves and deform | transforms in order in the circumferential direction.

<Sixth Embodiment>
FIG. 9 is an explanatory diagram of the hydraulic shock absorber 1 according to the sixth embodiment.
Note that in the sixth embodiment, members that are the same as in the other embodiments are given the same reference numerals, and detailed descriptions thereof are omitted.

  In the hydraulic shock absorber 1 of the sixth embodiment, the structure of the sixth applying member 991 of the bottom piston portion 40 and the nut 942 (an example of a holding portion) of the fixing member 944 is the same as the applying member 433 and the fixing member of the first embodiment. 44 different from the nut 442.

The sixth imparting member 991 is a substantially disk-shaped member having an opening 991H through which the fixing member 944 is passed inward in the radial direction. The sixth applying member 991 includes an oil passage port 991Y through which oil can pass and an annular portion 991R having a contact end E6 that contacts the check valve 431. The sixth applying member 991 applies a load that is uneven in the circumferential direction and directed toward the valve seat 41 to the check valve 431, as will be described later.
In the sixth embodiment as well, the contact end E6 is in contact with the check valve 431 in a range radially outward from the inner round portion 415 and radially inward from the outer round portion 416.

  In the nut 942, the height of the one side surface 942M is not uniform in the circumferential direction. That is, the first surface M1 on the one side surface 942M has a first protrusion amount H1 that protrudes toward one side with respect to the virtual line VL (for example, the other side surface 942L of the nut 942). On the other hand, the second surface M2 at a position different from the first surface M1 in the circumferential direction has a second protrusion amount H2 in which the amount protruding toward one side with respect to the virtual line VL is larger than the first protrusion amount H1. ing. That is, the nut 942 is different in the circumferential direction with respect to the sixth imparting member 991 and the check valve 431.

  In the bottom piston portion 40 of the sixth embodiment configured as described above, when the check valve 431 opens the extension side oil passage 413, the check valve 431 is separated from the round surface 41P (see FIG. 3A). Timing is different in the circumferential direction. Also in the sixth embodiment, the check valve 431 is moved and deformed in order in the circumferential direction, so that the generation of sound is further suppressed.

<Modification>
FIG. 10 is an explanatory diagram of a giving member 933 according to a modification.
As shown in FIG. 10, the application member 933 according to the modification includes an opening 933 </ b> H, a first circumferential protrusion 933 </ b> A, a second circumferential protrusion 933 </ b> B, and a held part 933 </ b> R.

The first circumferential protrusion 933A is circumferential and protrudes toward one side. A plurality of first circumferential protrusions 933A are provided and are arranged at substantially equal intervals in the circumferential direction. And 1st circumferential direction protrusion part 933A contacts the surface of the other side of the check valve 431 in the contact end part E7.
Note that the contact end E7 of the first circumferential protrusion 933A of the application member 933 according to the modification is located on the radially outer side of the inner round part 415 and in the radial inner side of the outer round part 416. (See FIG. 3A).
The second circumferential protrusion 933B protrudes toward the other side in the circumferential direction.

  The application member 933 of the modified example configured as described above may be used instead of the application members of the first to sixth embodiments described above.

For example, in the held portion 433R of the first embodiment, the strength in the circumferential direction of the held portion 433R may be changed by changing the plate thickness of the plurality of shape portions.
Further, for example, the configuration in which the strength in the circumferential direction of the held portion is different in the held portions (held portion 433R, held portion 533R) of the first embodiment and the second embodiment is the outer protruding portion of each embodiment. You may apply to. For example, the load, which is unequal in the circumferential direction of the check valve 431 and directed toward the valve seat 41, may be applied to the check valve 431 by changing the width, interval, and thickness of the plurality of outer protrusions.

  Further, in each of the applying members of the first to sixth embodiments, the circumferential direction of the check valve 431 is made by making the lengths of the plurality of outer protrusions in the radial direction (the amount of protrusion toward the outer side in the radial direction) different. , The load toward the valve seat 41 may be applied to the check valve 431.

  For example, in the first embodiment, the second outer protrusion 433B protruding toward the opposite side to the check valve 431 is not an essential configuration. Instead of the second outer protrusion 433B, a first outer protrusion 433A may be provided, and the first outer protrusions 433A may all be arranged at predetermined intervals in the circumferential direction on the outer periphery of the applying member 433. The same applies to other embodiments and modifications.

  In addition, the structure of the bottom piston part 40 of 1st Embodiment-6th Embodiment is the piston which moves with the movement of the rod 20 while dividing the inside of the cylinder 11 into the 1st oil chamber Y1 and the 2nd oil chamber Y2. You may apply to the part 30. FIG. Specifically, the check valve portion 43 of the bottom piston portion 40 can be applied instead of the configuration of the spring 33 and the piston valve 32 of the piston portion 30.

  In addition, although the hydraulic shock absorber 1 of the first to sixth embodiments has a so-called triple pipe structure, the configuration of the present embodiment may be applied to a so-called double pipe structure.

  Further, for example, the configuration of the bottom piston portion 40 of the first embodiment may be provided separately from the cylinder portion 10 and may be provided in an external storage portion that stores oil. In this case, it is only necessary to generate a damping force in the external housing portion with respect to the oil flow generated as the rod 20 moves in the cylinder portion 10.

DESCRIPTION OF SYMBOLS 1 ... Hydraulic shock absorber, 11 ... Cylinder (example of cylinder), 20 ... Rod (example of rod), 40 ... Bottom piston part, 41 ... Valve seat (example of piston), 431 ... Check valve (example of valve), 432 ... Check valve stopper (an example of a restriction part), 433 ... Giving member (an example of an imparting part)

For this purpose, the present invention has a cylinder that contains a fluid, a piston that forms a flow path through which the fluid flows as the rod moves relative to the cylinder in a predetermined direction, and has elasticity. has a valve for opening and closing the flow passage, and a movement permitting portion for permitting movement of the position of the valve between a spaced position away from the piston as a contact position in contact with the piston, the elastic, circumferential of the valve The applying portion for applying a load toward the piston to the valve, which is unequal in the direction, and the applying portion are provided separately from each other, and in an annular contact with the valve at the separated position. And a restricting portion that restricts movement inward in the radial direction .
In addition, for this purpose, the present invention includes a cylinder that contains a fluid, a piston that forms a flow path through which the fluid flows as the rod moves relative to the cylinder in a predetermined direction, and has elasticity. A valve that opens and closes the flow path, a movement allowing portion that allows movement of the position of the valve between a contact position that contacts the piston and a separated position that is separated from the piston, and the valve at the separated position. A restricting portion that restricts bending deformation, and an imparting portion that has elasticity and imparts a load that is uneven in the circumferential direction of the valve and that is directed toward the piston side to the valve. A pressure buffering device having a plurality of outer protrusions extending radially outward and contacting the valve, and an inner protrusion protruding radially inward between the plurality of outer protrusions A.

For this purpose, the present invention has a cylinder that contains a fluid, a piston that forms a flow path through which the fluid flows as the rod moves relative to the cylinder in a predetermined direction, and has elasticity. A valve that opens and closes the flow path, a movement allowing portion that allows movement of the position of the valve between a contact position that contacts the piston and a separation position that is separated from the piston, and has elasticity, and has a circumferential direction. in the applying unit for applying a load towards the piston side a unequal to the valve, provided separately from said imparting portion, of the valve in contact with the valve and annular in said spaced position And a restricting portion that restricts movement in a direction further away from the separation position with respect to the piston on the radially inner side.
In addition, for this purpose, the present invention includes a cylinder that contains a fluid, a piston that forms a flow path through which the fluid flows as the rod moves relative to the cylinder in a predetermined direction, and has elasticity. A valve that opens and closes the flow path, a movement allowing portion that allows movement of the position of the valve between a contact position that contacts the piston and a separated position that is separated from the piston, and the valve at the separated position. A restricting portion that restricts bending deformation, and an imparting portion that has elasticity and imparts a load that is uneven in the circumferential direction of the valve and that is directed toward the piston side to the valve. A pressure buffering device having a plurality of outer protrusions extending radially outward and contacting the valve, and an inner protrusion protruding radially inward between the plurality of outer protrusions A.

Here, in the first embodiment, the contact position is a position where all of the check valves 431 are in contact with the round surface 41P. In addition, the separation position is a position where all of the check valves 431 are separated from the round surface 41P.
Note that the movement of the position of the check valve 431 can also be regarded as the displacement of the check valve 431 as a whole in the axial direction. In this case, the movement of the position of the check valve 431 can be regarded as a displacement in a state where the check valve 431 is not deformed.
Further, the deformation of the check valve 431 means that the radially outer side (at least the opposite part of the second other-side oil passage port P2) is deformed in a state where the radially inner side (opening portion 432H side) is located at the separated position. It can also be captured.

Claims (9)

A cylinder containing fluid;
A piston that forms a flow path through which fluid flows with relative movement of the rod in a predetermined direction with respect to the cylinder;
A valve having elasticity and opening and closing the flow path of the piston;
A movement allowing portion that allows movement of the position of the valve between a contact position that contacts the piston and a separated position that is separated from the piston;
A restricting portion for restricting the bending deformation of the valve at the separated position;
An imparting portion that has elasticity and imparts a load to the valve that is uneven in the circumferential direction of the valve and directed toward the piston;
A pressure buffering device.   The pressure buffering device according to claim 1, wherein the applying portion has different strength in the circumferential direction.   The pressure buffering device according to claim 1, wherein the applying portion includes a plurality of outer protrusions extending radially outward and includes a contact portion that contacts the valve.   The pressure buffering device according to claim 3, wherein the contact portion includes a plurality of the outer protrusions having different contact positions in the radial direction of the valve.   The pressure buffer device according to claim 3, wherein the contact portion includes a plurality of the outer protrusions having different distances from the valve.   The pressure buffering device according to claim 3, wherein the applying portion includes an inner protrusion that protrudes radially inward between the plurality of outer protrusions. A holding part for holding at least the valve and the restriction part on the piston;
The pressure buffering device according to claim 1, wherein the holding portion includes the movement allowing portion having a different distance from the valve in a circumferential direction. The piston includes an inner annular portion that protrudes annularly on the radially inner side of the flow passage port of the flow passage, and an outer annular portion that protrudes annularly on the radially outer side of the flow passage port,
The pressure buffer device according to claim 1, wherein the imparting portion is outside the inner annular portion and contacts the valve inside the outer annular portion.   The valve restricts the flow of fluid through the flow path during relative movement of the rod in a predetermined direction, and allows the flow of fluid through the flow path during relative movement of the rod in the reverse direction. The pressure buffer according to claim 1, wherein the pressure buffer is a check valve.

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